Steam-boiler setting



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STEAM BOILER SETTING. No. 426,255. PatentedAp-r. 22, 1890. V

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W. U. FAIRBAIRN. STEAM BOILER. SETTING.

No. 426,255. Patented Apr. 22, 1890.

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W. U. PAIRBAIRN. STEAM BOILER SETTING. No. 426,255. Patented Apr. 22',1890.

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UNITED STATES PATENT OFFICE.

\VILLIAM U. FAIRBAIRN, OF HYDE PARK, MASSACHUSETTS.

STEAM-BOILER SETTING.

SPECIFICATION forming part of Letters Patent No. 426,255, dated April22, 1890.

Application filed September 21, 1889. Serial No. 324,607. (No model.)

To aZZ whom, it may concern:

Be it known that I, WILLIAM U. FAIRBAIRN, of Hyde Park, in the county ofNorfolk and State of Massachusetts, a citizen of the United States, haveinvented a new and useful Improvement in Steam-Boiler Setting, of whichthe following is a full, clear, and exact description, reference beinghad to the accompanying drawings, forming a part of this specification,in explaining its nature.

This improvement is designed to effect a more perfect combustion of thefuel employed to heat steam-boilers and to utilize as much as possibleof the heat generated.

Much of the construction hereinafter referred to or described has beenalready described in Letters Patent granted to me March 27, 1888, No.380,197, and the improvements on the apparatus described in said LettersPatent are mainly in and around the fire-box.

In the drawings, Figure 1 is a transverse section across the fire-boxjust in front of the bridge-wall. Fig. 2 is a longitudinal sectionthrough the fire box and the flue beneath the boiler adjacent to thefirebox. Sis a front elevation of the fire-box; and Figs. 4 and 5illustrate a method of automatically feeding fuel to the fire-box, whichin some instances and for some purposes I am inclined to prefer to theArchiinedean screw shown in Fig. 3.

Like letters indicate like parts in all the figures.

111 the drawings, A is the boiler, and B is the flue under the boiler.The flame returns through internal tubes, as is usual in boilers, and Dis the uptake which leads to the stack. F is the fire'box.

G is the bridge-wall interposed between the fire-box and the flue Bbeneath the boiler. The bridge-wall. is pierced with the convergingupwardly-directed fluesf, as described in the patent referred to, andthe walls of the fire-box are pierced with air-channels g, (shown indotted lines in Fig. 2,) all substantially as shown in the patentreferred to.

The fire-box F of the present contriyance has in lieu of the ordinaryfire-front of a boiler-setting a front, as shown in Fig. 2, consistingof a series of slats, each of which is pivoted to the walls of thefirebox or to sockets fixed thereon, the line of the axes being somewhatinclined from the vertical. These pivoted slats are marked K in Fig. 2.They are connected to the slat-rod by links or pivots, very much as theoscillating slats of a window-blind are connected to the slat-rod ofthe. window-blind, and this slatrod k is attached to the lifting-shaftL, which in Fig. 2 is shown as a hand-wheel and screw-rod with a swivelon its end, by which the series of slats K may be oscillated severallyupon their centers, and by such oscillation caused either to lap uponeach other, so as to prevent the passage of air into the fire-boxthrough the front thereof, or to permit more or less air to pass betweenthe slats. The interval between the hubs of these slats which fit uponthe pivots may be considerably greater than is shown, so as to allow ofconsiderable passage of air, if desired.

It will be observed that when the slats are horizontal, or nearly so,there is a considerable interval m beneath the lowest of them, throughwhich the bed of coals resting on the grate bars a may be sliced orpoked. There is a man-hole 0, with a cover 0', on the top of thefire-box, through which, if desired, coal may be fed. The hopper 12extends across the whole width of the fire-box on top, and the bottom ofthis hopper is connected by a manhole 1) with the front part of thefirebox F. This man-hole p is closed at its bottom by a swinging shelf1)", which can be oscillated on a pivot at one corner, and when throwndownward toward the perpendicular will dump the charge of fuel which isabove the swinging shelf into the fire-box. A trough (1 (shown in Fig.3) continues from this hopper 19 in the direction of a coal-bunker,which delivers fuel into the trough, and this fuel is moved along thetrough to the hopper p by means of the Archimedean screw 0', which isset in motion as desired. It is sometimes desirable, in burninghighly-combustible fuel, to stop the generation of steam rather than togenerate the steam in the boiler and blow it off, when work is shutdown, through a safety-valve. In order to do this it is desirable toprevent the gases of combustion from passing under the boiler andthrough the tubes. This may readily be done by an auxiliary flue placednear the fire-box in the bottom of the boilerflue 13, which auxiliaryflue is in constant communication with the uptake, but may be put incommunication with the boiler-flue B or not, as the operator may desire.In the drawings, Fig. 2, S is such an auxiliary flue, which is carriedthrough the masonry beneath the boiler-flue B to the uptake, and has aflue of proper size 8 communicating with the boiler-flue B. A damper s,operated from outside the casing by any convenient sort of handle, opensor closes the communication between the flue s and the boiler-flue B atthe will of the operator.

In the bottom of the fire-box F grate-bars n of the ordinary characterare placed, and there is the usual ash-pit T beneath the firebox, withthe usual ash-hole tand ash-door t.

In Figs. 4 and 5 is shownin Fig. 4' a longitudinal section and in Fig. 5a plan-a coal-feeding apparatus somewhat difierent from that illustratedin Figs. 2 and 3. The

hopper p, with its man-hole p and swinging shelf 19 are still retained;but the means of feeding coal to the hopper differ from those alreadydescribed, and the coal is dumped into the fire-box at regularintervals. The swinging shelf 19 is mounted on a shaft 19 which ispivoted in the side of the hopper, and on one end of this shaft is aweighted lever 19, which serves to counterbalance the swinging shelf andthe coal which may be deposited upon it. On the opposite side of theshaft from the weighted arm 19 is a projection 19 and this projection istripped from time to time by one of the pins u in the wheel it. Thiswheel 16 is carried upon a shaft U, (shown in Fig. 4,) which shaftrevolves in hearings on the outside of the hopper p and is driven by oneof the cone-pulleys U. Above this shaftU is another shaft V. Atrough p,in continuation of the hopper 10, extends toward a coalbunker 19 whichterminates downward in a hopper-shaped delivery end, and near the bottomof this hopper-shaped delivery end is placed another shaft V, which hasa set of cone-pulleys Q; on one end, which engage with the cone-pulleysU upon the shaft U, and at the other end a set of cone-pulleys 'v', towhich power is applied from the engine or prime motor. By this system ofgearing any desired rate of speed may be given from the prime motor tothe shaft V, and from that shaft to the cone-pulleys U. An endlesselevator-belt WV, carrying vanes, is placed around the shafts V V, oraround drums upon said shafts, and a diaphragm 19 extends from side toside of the trough p, below the upper member of this endless belt. Thespeed at which the shaft V s revolved will determine the speed at whichcoal is taken from the bunker p and carried to the hopper p. The numberof times that the coal will be dumped in a given period will depend uponthe number of pins u in the wheel a or on the speed of revolution of theshaft U. This speed of revolution can be governed Within reasonablelimits. by shifting the belt between the shafts U and V to differentdiameters of the cone-pulleys carried on said shafts. I am inclined toprefer this method of feeding for the fire-boxes of a single boiler; butI think the Archimedean screw would be preferable for the fire-boxes ofa gang of boilers.

By feeding the fuel, particularly if it bean easily-volatilizcd fuel,into the Very front of the fire-box, it will fall upon the ends'rof theslats of the fire-front and will be partly sup ported by them inconsequence of the inward inclination of the line of pivots, so that allalong the edge of these slats there will be a comparatively thin layerof the freshest fuel admitted to the fire-box. This fuel can havesufficient air supplied to it through the interstices of the fire-frontto properly distill it and volatilize it to the condition of carbonicoxide and carbonated hydrogen, but little carbonic acid being formed,and this gas thus made and highly incandescent will go forward throughthe fines f, and on reaching the main boiler-flue B will be furnishedwith the highly-heated air necessary for complete combustion arriving atthis point through the air-ducts but such perfect and completedistillation of the fuel will not take place if the fire is fedaltogether through the man-hole 0, which is nearer the bridge-wall thanthe man-hole p, and without the ability inherent in this form of slattedfire-front to control the admission of air to this fresh fuel as it isdrying and distilling the distillation would be less efiicient and thecontrol of the quality of the products of distillation much less nicethan it is with the apparatus here shown.

I claim as my invention and desire to secure by Letters Patent 1. Thecombination of the fire-box F with the fire-front K, composed of a blindof pivoted slats combined with each other 7 and adapted to be operatedin unison by means of the slat-rod k and suitable actuating mechanism,substantially as described.

2. The combination of the fire-box F, its fire-front K, composed ofpivoted slats adapted to be oscillated upon their centers, and hopper19, man-hole p, and dumping-flap 12 substantially as described.

3. The combination of the wheel u, its pins to, with the hopper p,swinging flap p and weighted lever 19 provided with the trip psubstantially as and for the purpose described.

WILLIAM U. FAIRBAIRN.

Witnesses:

F. F. RAYMOND, 2d, J. M. DOLAN.

